Process control systems are designed to control process-based installations and possess process-oriented components which are connected via a bus system to the components of the process to be managed or, as the case may be, controlled/regulated, such as, for example, actuators or sensors. In most cases the process control system has a control and monitoring station coupled to the bus system so that manual intervention in the process flow will be possible if the need arises.
The logic of the process control system (PCS) resides in the process-oriented component in the form of a computer program, hereinafter also referred to as a PCS program. According to the prior art, PCS programs of said type are programmed in an engineering system which provides different programming languages and editors for the standard automation functions and is directly connected to the process control system. Process control algorithms that are particularly complex mathematically or, as the case may be, sophisticated control and regulation techniques, on the other hand, are initially implemented and tested in a separate development and simulation environment which is physically separate from the process control system and also cannot exchange any data with said system. The development environment comprises a computer on which development and simulation software established for example under the Windows® operating system runs. A frequently deployed software package in this regard is called MATLAB/SIMULINK® and originates from the company MathWorks based in Natick, Mass., USA.
However, programs created using MATLAB/SIMULINK® are intended for processing by microprocessors of the Intel family under MS Windows without realtime requirements. For this reason they cannot be processed by the hardware of a process control system. Rather, it is necessary, upon completion of the preliminary work in the simulation environment, to re-implement the program created using MATLAB/SIMULINK® in a programming language that is available for the particular process control system.
This re-implementation cannot always be accomplished, in particular with complex control procedures or also with mathematically complex process control methods. One reason is that the hardware of the process control systems is limited in terms of its performance and to that extent quickly reaches its limits in such cases with regard to its computing power and its memory space. Another reason is that the above-mentioned compilers for process control systems, for example those for the high-level language SCL (Structured Text as defined in IEC 1131-3), do not have mathematical software libraries, e.g. for numerical techniques or matrix operations, in contrast to the above-mentioned MATLAB/SIMULINK® software package. Accordingly it is necessary to invest great effort, time and cost into reproducing missing libraries.